The present invention relates to communications access networks, and in particular to Voice-over Digital Subscriber Line customer premises equipment and services provision.
Reference is made to applicants co-pending applications of the same date and titled xe2x80x9cImproved VoDSL Service Provisionxe2x80x9d (our reference 10868ID: Czajkowski) and xe2x80x9cEnhanced VoDSL Service Provisionxe2x80x9d (our reference 10850ID: Czajkowski). The contents of these applications are intended to be incorporated herein.
Telephone access networks have historically always been connection orientated, typically using dedicated copper wire circuits between subscribers and the exchange or central office. Typically these access networks were designed to carry only voice with a bandwidth of less than 4 kHz. However in recent years with the growth of the internet and demand for other multi-media services such as video-on-demand and video conferencing, subscribers of telephone companies have demanded additional bandwidth over the access network to provide adequate internet and multi-media services access.
The Integrated Services Digital Network (ISDN) protocol was developed as an access network architecture for delivering all types of services including voice, data and video for example. Although ISDN provides a single access technology, it is limited by offering only xe2x80x9cnarrow bandxe2x80x9d communications speeds and relatively high pricing for terminal equipment and network access. This, together with the lack of xe2x80x9cimaginativexe2x80x9d residential services that could capitalize on the underlying bandwidth capacity, has seen the technology being confined to larger business customers.
Digital Subscriber Line (DSL) modem technology has enabled the transmission of digital information at duplex rates from 144 Kbits/s to over 1 Mbits/s over the local subscriber loop consisting of unshielded twisted pair cable. Reference is made to IEE Electronics Communication Engineering Journal, Vol. 11, No. 3, Page 125 (June 1999) for additional background on DSL technology. The demand for additional telephone lines and integrated telephony and data services has given rise to voice-over DSL (VoDSL) solutions, which use modem technologies to deliver services in-band over a single physical line. For example, a VoDSL offering may provide a Customer Premises Equipment (CPE) functionality with 4 POTS (Plain Old Telephony Service) ports, each with a unique telephone number, and an ethernet port for high speed data access to an Internet Service Provider (ISP). All the POTS (typically voice or fax conduits) lines are provided as digitally derived services. VoDSL is an emerging technology, and as such requires subscriber acceptance and take-up both for the future development of this technology and to repay access network operator investment in the VoDSL equipment.
It is an object of the present invention to provide improved VoDSL equipment functionality and performance.
It is a further object of the present invention to provide improved quality of service for derived voice telephony calls provided over a DSL link, above that normally available with VoDSL.
It is a further object of the present invention to provide the subscriber of VoDSL access networks with improved services capability.
In a first aspect the present invention provides Digital Access System (DAS) Customer Premises Equipment (CPE) comprising:
an internal packet switched network comprising a switch;
a DAS modem connected to said internal network and arranged such that in use the internal network is coupled to an external packet switched network by a DAS link over an access network;
a controller arranged to control said switch in order to establish packet transfer paths between said modem and one or more internal network interfaces to customer appliances connected to the CPE in order to complete calls between said appliances and entities on the external network;
wherein the CPE is arranged to reconfigure parameters corresponding to a first layer dependent on parameters corresponding to a second layer.
Preferably said DAS is Voice over Digital Subscriber Line (VoDSL).
Preferably one of said layer is the physical layer.
Preferably said CPE further comprises means for enabling cross-layer cognizance between the modem and the controller in order to optimize quality of service for one or more derived digital embedded voice calls carried by said DSL link CPE performance.
Preferably said cross-layer cognizance means comprises means for forwarding packet transfer path and/or voice call state information from the controller to the modem and forwarding DSL link information from the modem to the controller.
Preferably said forwarding means comprises an application programmers interface enabling function associated with the modem and a corresponding application programmers interface enabling function associated with the controller which together form an application programmers interface (API).
Preferably said API is established over a packet transfer path on said internal network.
Preferably said cross-layer cognizance means comprises a computer function arranged to reconfigure the modem and the controller dependent on said forwarded information.
Preferably said CPE comprises said computing function.
Alternatively said computing function is external to said CPE. Preferably said computing function is associated with a Personal Computer connected to said network-data interface.
Preferably said controller is a control processor.
Preferably one of said layers is the link layer. Preferably said link layer is ATM.
Preferably one of said layer is a layer corresponding to end to end voice call control and admission across said DSL link.
In a second aspect the present invention provides DAS Line Terminating Equipment (LTE) comprising:
an internal packet switched network comprising a switch and forming part of an external packet switched network;
a DAS modem connected to said internal network and arranged such that in use the internal network is coupled to a Customer Premises Equipment (CPE) internal packet switched network by a DAS link over an access network;
a controller arranged to control said switch in order to establish packet transfer paths between said modem and gateways or destinations on the external network;
wherein the LTE is arranged to reconfigure parameters corresponding to a first layer dependent on parameters corresponding to a second layer.
Preferably said DAS is VoDSL.
Preferably one of said layers is the physical layer.
Preferably said LTE further comprises means for enabling cross-layer cognizance between the modem and to the controller in order to optimize LTE performance.
Preferably one of said layers is the link layer. Preferably said link layer is ATM.
Preferably one of said layers is a layer corresponding to end to end voice call control and admission across said DSL link.
In a third aspect the present invention provides an access network comprising:
a physical medium connecting DAS Line Terminating Equipment (LTE) to Customer Premises Equipment (CPE);
said LTE comprising:
an internal packet switched network comprising a switch and forming part of an external packet switched network;
a DAS modem connected to said internal network and arranged such that the internal network is coupled to a CPE internal packet switched network by a DAS link over said physical medium;
a controller arranged to control said switch in order to establish packet transfer paths between said modem and gateways or destinations on the external network;
wherein the LTE is arranged to reconfigure parameters corresponding to a first layer dependent on parameters corresponding to a second layer; and
said CPE comprising:
said CPE internal packet switched network comprising a CPE switch;
a CPE DAS modem connected to said CPE internal network and arranged such that the CPE internal network is coupled to said external packet switched network by said DAS link over said physical medium;
a CPE controller arranged to control said CPE switch in order to establish packet transfer paths between said CPE modem and one or more internal network interfaces to customer appliances connected to the CPE in order to complete calls between said appliances and entities on the external network;
wherein the CPE is arranged to reconfigure parameters corresponding to a third layer dependent on parameters corresponding to a fourth layer.
Preferably said DAS is VoDSL.
Preferably said third layer is said first or second layer and wherein said fourth layer is said second or first layer.
In a fourth aspect of the present invention provides an improved method of operating a VoDSL CPE or LTE comprising:
an internal packet switched network comprising a switch;
a DSL modem connected to said internal network and arranged such that in use the internal network is coupled to an external packet switched network by a DSL link over an access network;
a controller arranged to control said switch in order to establish packet transfer paths between said modem and one or more internal network interfaces to customer appliances connected to the CPE in order to complete calls between said appliances and entities on the external network;
the method comprising:
determining parameters corresponding to a first layer;
reconfiguring parameters corresponding to a second layer dependent on said first layer parameters.
In a further aspect the present invention provides a method of operating a VoDSL CPE or LTE for delaying modem retraining when voice calls in progress, said CPE comprising:
an internal packet switched network comprising a switch;
a DSL modem connected to said internal network and arranged such that in use the internal network is coupled to an external packet switched network by a DSL link over an access network;
a controller arranged to control said switch in order to establish packet transfer paths between said modem and one or more internal network interfaces to customer appliances connected to the CPE in order to complete calls between said appliances and entities on the external network;
the method comprising:
determining whether the margin has fallen below a first predetermined threshold;
if so, determining whether voice calls are in progress;
if not, begin retraining;
if, so determining whether margin has fallen below a second predetermined threshold;
if so, begin retraining.
In a further aspect, the present invention provides a Digital Access System (DAS) Customer Premises Equipment (CPE) comprising:
a Digital Subscriber Loop (DSL) physical layer;
a packet switching layer; and
a data/voice layer,
wherein said CPE is arranged to reconfigure parameters corresponding to a first of said layer dependent on parameter corresponding to a second of said layer.
In a further aspect, the present invention provides a DAS Line Terminating Equipment (LTE) comprising:
a Digital Subscriber Loop (DSL) physical layer;
a packet switching layer; and
a data/voice layer,
wherein said CPE is arranged to reconfigure parameters corresponding to a first of said layer dependent on parameter corresponding to a second of said layer.
In a further aspect, the present invention provides a DAS network comprising CPE and LTE each comprising:
a Digital Subscriber Loop (DSL) physical layer;
a packet switching layer; and
a data/voice layer,
wherein said network is arranged to reconfigure parameters corresponding to a first layer of one of said CPE and LTE dependent on a parameter corresponding to a second layer of one of said CPE and LTE.